The present disclosure is directed to monomers and methods for making monomers for forming electrically conductive polymers.
Electrically conducting polymers have found use in a variety of organic optoelectronics applications. Such optoelectronic applications include polymeric light emitting diodes (thin film displays), solid-state lighting, organic photovoltaics, advanced memory devices, organic field effect transistors, ultracapacitors, electroluminescent devices, printed electronics, conductors, lasers, and sensors.
One of the first electrically conducting polymers was polyacetylene and the discovery of conductivity in such polymer created substantial interest in other types of electrically conducting polymers. Recently, conjugated poly(thiophenes) and substituted thiophene derivatives have been discovered to have electrically conducting properties. A feature of these polymers is that they can be cast into films and doped with conventional p- and n-type dopants. Additionally, the doped polymers can be cast into films and their electrical properties modified accordingly, thereby lending themselves suitable for use in a variety of optoelectronic applications.
Known thiophene monomers and electrically conducting polymers including thiophene and derivatives thereof include the following:
U.S. Patent Application Publication No. US2004/0010115A1 to Sotzing discloses homopolymers and copolymers comprised of repeating units of thieno[3,4-b]thiophene for use in electroactive applications. The thieno[3,4-b]thiophene compounds disclosed in the US2004/0010115A1 include the following structure:

U.S. Patent Application Publication No. US2004/0010115A1 further discloses that copolymers can be formed with compounds including 3,4-ethylendioxythiophene, dithiophene, pyrrole, and benzothiophene.
U.S. Pat. No. 6,645,401 to Giles et al. discloses conjugated polymers of dithienothiophene (DTT) with vinylene or acetylene connecting groups as suitable for producing semiconductors or charge transport materials useful in electrooptical and electronic devices including field effect transistors (“FET”), photovoltaic, and sensor devices.
U.S. Pat. No. 6,585,914 to Marks discloses fluorocarbon-functionalized and/or heterocyclic modified poly(thiophenes) such as α, ω-diperfluorohexylsexithiophene for use in forming films, which behave as n-type semiconductors. These poly(thiophenes) also can be used to form thin film transistors with FET mobility.
U.S. Pat. No. 6,676,857 to Heeney et al. discloses polymers having polymerized units of 3-substituted-4-fluorothiophene as liquid crystal materials for use in semiconductors, charge transport materials, electrooptical field effect transistors, photovoltaic and sensor devices.
U.S. Pat. No. 6,695,978 to Worrall et al. discloses polymers of benzo[b]thiophene and bisbenzo[b]-thiophene and their use as semiconductors and as charge transport materials in electrooptical devices.
U.S. Pat. No. 6,709,808 to Lelental et al. discloses image-forming materials incorporating electrically conductive polymers based upon pyrrole-containing thiophene polymers and aniline containing polymers.
Tetrahedron 1940, 36, 3317-3324 by Gronowitz discloses the preparation of seleno(3,4-b)selenophene. The synthesis utilizes a decarboxylation procedure that is commonly seen as being problematic if exploited at a commercial scale.
Heterocycles 1997, 45, 1891-1894 discloses the preparation of selenolo(2,3-c)thiophene by a multistep route. Multistep routes have been shown to be useful for synthesizing materials at small scale, but are generally not favored for large scale, industrial setups.
While the above references include disclosures of known monomer compounds and methods of making these known monomer compounds, none of the above references discloses substituted seleno(3,4-b)selenophenes, seleno(2,3-c)thiophenes, or thiophene(3,4-b)selenophenes monomers or methods of making fused selenophene monomers of the present disclosure.
The disclosure of the foregoing patents, patent applications and publications is hereby incorporated by reference in their entirety.
What is needed is a monomer capable of forming an electrically conductive polymer for a wide range of electronic applications. There is also a need in this art for a monomer that can be formed using readily available, easily handled reagents and which can be polymerized.